Air conditioning unit



5, H. J. FlNDLEY AIR CONDITIONING UNIT Filed Sepi. 28, 1939 2 Sheets-Sheet 1 I INVENTOR Howaeo J. HMJLEY BY v ATTORNEY Nov. 25, 1941. H. J. FINDLEY AIR CONDITIONING UNIT 3 Sheets-Shet 2 Filed Sept. 28, 1939 INVENTOR lfowmvo JHNDLEY BY $4M ATTORNEY ,the interior surface of the-windshield'flfl'hus by a more suitable location of moving Y Patented Nov. 25,1941

UNITED STATES ,PATENT" OFFICE I i v ates-:23 I

smcoum'r omo nmr Howard J. Findley, andid, Ohio, assignor to Eaton Manufacturing Co mpany, Cleveland,

Ohio, a corporation of Ohio Application September 28, 1939, Serial No. 296,921 4 Claims. (01. 257-137) .The present invention relates to heat eitchangers, and more particularly, concerns a means forproviding tempered air in a vehicle passenger compartment adjacent the vehicle windshield so as to maintain the same substantially clear under all weather conditions.

Heretofore in this art the better passenger compartment heaters for vehicles have generally been provided with valve means for by-passing a portion or,all of the heated air through one phere.

or more conduits to the windshield for effecting removal of fog, ice or snow. The large volume and pressure of tempered air required was generally deficient and performed unsatisfactoriiy because of the inherent nature of the heater structure and e a the tortuous restricted passage imposed upon the air transfer. More recently the development of heaters has been directed toward the-use of two 1 fans, mountedat one or the opposite ends of a motor, upon a common drive shaft, Certain of these heaters were arranged so that both air impellers wereoperated under full load at all times, one fan being used for heating the vehicle and the other used for air delivery to the 7 windshield. Otherconstructions provided'means,

for clutching or declutching the windshield fan when nominally required, or'means providing a reversible driving motor. and fixing the'fans in reverse relation to each other, so thatonly one .fan was under load at a time and the drain on 'the electrical system was at aminimum. However, these structures have proved deficient because while sufiicient air was deiivered to the surface of thewindshield. the delivered to I the passenger compartment asa-whole' was not, uniform enough and resulted ina hot blast '01 air in spots adjacent-the delivery face of'the "vehicle compartment.

at substantially close to or below freezing atmos- The use of -a conventional windshield heater or defroster causes a rise in the facetemperature of the windshield sufficient to partially melt the snow, and operation of th'e'vehicle at even normal and especially at fast speeds, in view of the temperature differential existing between the inside and outside surface of the. windshield,jresults in the ready freeze up of the snow rendering the wiper blade useless. On the other hand, the failure to use the windshield heater, or discharge of a stream of air across the wind-'- shield surface, results in the fogging of the windshield as the warm moist air of the closed passenger compartment gravitates towards the cooler windows and deposits its moisture thereon. However, if a quantity of cool dry air from outside the vehicle is blown across theinner face of the windshield the "dry .snow, under the above atmospheric conditions, will not be melted and may be brushed on clean by the 'wiperor blown oil in transit bymovement through the advancing air stream. Likewise, fresh air reduces the tendency of the windshield to fog by lowering the relative humidity of the Accordingly, the primary object of this invention is the provision of a new and novel vehicle heaterand arelatively starved. quantity. of heatto the rearv compartment; "Therefore; the most heating andthe movementoi air 0v unit and adherence to a single for emciency in-each case has been effected.

recent, and apparently trend, has bee v to provide separate units for the. compartment The present invention has provided a novel I I solution of a, vexihgproblem encountered when .driving infcertain' weather conditions, of course the heater is'equally well adapted for use under ordinary winter weather conditions when units of this type arevThat is to. say, when operating a vehicle under-weather conditions causing a relatively dry snow storm and windshield heater and air moving structure including a novel compact heater core element and air box associated therewith for collecting fresh outside air received through a conduit in reto forward motion of the vehicle.

Other objects of thelinventioninclude the provision -in a windshield heater as above described of means providing a heater core element composed of a single continuous core tube with a series of separate heat radiating fins assem bled thereon in spaced relation, including an unit closely associatedwith one face'of said eore element, and an air collecting ;.box'adjacent the'0DP08ite facethereo'f for re ception of-ffresh outside'air forced'through a conduit, in communication withan air deflector member in the vehicle cowl wall, in response to forward motion of the vehicle; the provision in a'lvehicle windshield heater as above described of means for driving an air impellingunitassoelated therewith to accelerate the delivery'of tempered or untempered air through said heater casingflto the vehicle windshield; the'provision in a heater unit as above of valve means profor-selective use of fresh outside-air or recirculated heated a 'roidelivery to the inside face of the vehicle windshield, including other valve means located in the heater unit for selective by-passing of tempered air from the heater direct to the passenger compartment; the provision in a windshield defroster as above described, of means for by-passing fresh outside air from the air collecting box through the hollow center of the core element whereby untreated air may be distributed through conduits directly to the inner face of the vehicle windshield; the provision in a windshield defroster as above described of means for induction of fresh air from outside the vehicle and means comprising an air collecting box provided with air discharge outlets whereby to direct fresh outside air through an associated heater core element before passage to the vehicle windshield, and separate valve means in,the defroster unit for selectively diverting the fresh heated air directly to the passenger compartment adjacent the driver's feet for spot I heating.

Other objects of the invention include the provision in a windshield heater and defroster com- I I, a windshield l9, shown as of the divided type, and an instrument panel II. The heater and defroster assembly is shown generally at 20, it being understood that it is supported from the dash l and that the main flow of air therefrom is discharged through an enlarged opening 2| in its peripheral wall tangential thereto and into a Y-fitting 22 secured thereover. The auxiliary air stream from the heater is shown by way of illustration as being by-passed through a valve 24 which when open discharges into the passenger compartment adjacent the driver's feet. The Y- fltting 22 has communicating therewith the branches 26 leading to nozzle-like members 21 which project through openings therefor in the upper edge of the instrument panel l1 and in a position to direct the air blast therefrom against the inner face of the windshield IS on opposite sides of 'the center. A conduit 28 extends through a wall of the vehicle and on the outer end is connected to an'air deflector 29, which diverts fresh outside air thereinto under forward motion of the vehicle, while the inner end of the conduit 28 is in communication with an air colof in abutting relation and extending parallel to each other and normal to the circular conformation, including a series of individual apertured heat radiating fins assembled on said circular portion of the core element and integrally bonded thereto.

Otherobjects and advantages of the present invention will become apparent from the following specification, the drawings relating thereto, and from the claims hereinafter set forth.

In the drawinss'in which like numerals are used to d signate like parts throughout the several views: r Fig. 1 is a fragmentary elevational view of the interior of a vehicle having associated therewith a heating and defrosting unit embodying features of the-prwent invention;

Fig. 2 is a view in which the upper half is a verticaisection and the lower half is an elevation, taken substantially along the line 2-2 of Fig. 1; Fig. 3 is an enlarged'front elevational view with par-m broken away showing some of the interior t of the parts of the heater removed from the vehicle shown in Fig. 1;

Fig. 4 is an elevational view of the core structure removed from the heater shown in Fig. 1;

.Fig. 5 is an end elevational view of the core shown in Fig- Hg. 6 is an elevational view of a single core radiating fin removed from the core structure of 1'18- Fig. 7 is a vertical diametrical sectional view j Flg.8issnexplodedtopplanviewofthemain \mitsoi the'heater showing the same inzdised condition;

Fig. 10 is a side elevational view of the air box showninFlg.9. 7

Referring now to the accommnyins drawings, inI'IgJIsshownane-utomohflehaflngadash lecting box forming the rear face of the heater.

distribution in untempered condition to the surface of the windshield, in a manner to be hereinafter described. The valves 24 and 30 may both be closed and recirculated air may be drawn from the vehicle and heated before delivery to the windshield, or the'valve 24 be opened and valve ll be closed for delivery of heated recirculated air into the'passenger compartment adjacent the drivers feet.

Refen'ing now to Figs. 2 to v, inclusive, the heat exchanger or radiator core element per se comprises a single section of hollow tubing connected at the opposite ends thereof to a source of heat laden medium forming interconnected passages *for the flow .of heating medium therethrough. This heating medium may, of course, be any suitable substance but preferably in accordance with conventional constructions is either heated water from the internal combustion engine which drives the cooperating automobile or steam which is formed as a rwult of the operation of the engine. From an inspection of Fig. 4 and Fig. 5 it'will be seen that the core has no headers for distributing and collecting heating fluid, and the single core tube is of the round type although obviously it maybeflattenedorovalincrosssection. For purposes of illustration,, and more particularly for use in conjunction with the disclosed air circulating means, the specific radiator shown has been arranged from a single tube 32 shaped into a circular form around a hollow axis or center and the opposite ends of the tube bent normal to the plane of the circular body providing an inlet 34 andadischargeilitbeingundwStoodthatthetanguiar plates formed with, a central aperture 3!, the wall of which has been drawn down normal to the body of the plate and projects therefrom a short distance, as best shown in Figs. 6 and 7. The right and left hand sides ll and 42, respectively, of the fin 38 have been bent away from the main body of the plate and extend in substantially opposite angular relation.

to the body of the iln and parallel to each other for a reason to be presently explained. It will be understood that the fin is preferably made I of copper or other material having good heat radiating or absorbing qualities, and that the' rectangular plateis most economically stamped and blanked out on a suitable punch press. In

other in opposite directions and in spaced planes. A plurality of the flns 38 may now be threaded 4i and 42 of the iins are in close parallel and spaced nested relationship. After the requisite number of fins have been assembled on the tube, a space isreserved on either end for bending the tube at a'right angle to the plane of the circular body and for extension. of the exposed ends of the tube through the dash to be later connected to a source of heating medium. The

tinning composition or solution and thence into a liquid soldering solution where the fills are securely soldered to the tube.-- It will now be apparent that the. integral projection ll' serves onto the tube 32 through the aperture 39 of the iln with the integral projection 40 thereof in a directly-into the passenger compartment adjacentforward direction, whereby all the bent sections- '3 the outer periphery of the motor. A two' part shell or casing 48 and acomprises, respectively, an annular complementary shaped section for reception of the cone shaped end'of the blower wheel and an annular dished section serves as a cover for the opposite end of the blower wheel and a support for the motor. '48 and "a of the shell are adapted to be secured together around their opposed marginal edges of the parting line thereof by. any suitable means such as screws, spot welding or a snap ring over the adjacent opposed marginal edges.

The blower shell assumes the form of substantially an involute spiral trom which atthe greatest radius the enlarged opening 2| extends tangential thereto and over which is clamped or otherwise suitably secured the Y-iltting 22. A second opening into thehousing comprises the valve 24,

adjacent to opening 2|, whereby when open the air discharge fromthe heater may be diverted from the discharge opening II and delivered v the driver's feet.

,radiator assembly may be dipped 'in any suitable to accurately-and nicely space the fins 38 providing an air passage therebetween, while the. marginalangularly bent sections ll and 42 being in parallel relation present a tortuous radial inward passage to the entering, air causing a turbulence therein which provides an improved wiping or scouring action of the untreated air in going through the heattransfer process. An arcuate shaped member 44, coextensive with the width'of the fins 38, andwhich is soldered thereto, bridges the gap left by the spaced tube ends 34 and "3B completelycloses the hollow.

circular space within the radiator and defines an air chamber therethrough. Of course, while thevtube construction shown is formed into a single convolutiomand would not have the heat transfer capacity of a conventional heat exchanger employing a pair joi' spaced headers and a plurality of interconnected passages for the flow of heating medium between them, ,the number of convolutions of. the present radiator may be multiplied to secure any desired heating capacity, howevenior the present usethe. single convolution has provided ample capacity in a most compact and emcient manner for its size. The blower unit-generally designated is of .culator which are necessary to thecomplete understanding-of-the present invention are her in referredto and described in detail. More particularly'the blower unit' is composed of an air impeller l6 of the centrifugal blower type that is'operatively connected to a driving motor 41 througlrthe cone shaped'section thereof whereby the air impeller concentrically overlies f ing theseparate units into a compact assembly.

Other screw means 82 project through. the outer An air collecting box' generally designated 7 comprises a substantially flat annular bodypor- 3| and the blower unit 45 and terminates in an air intakeopening extending from the side thereof which tapers from the flat body portion to a relatively enlarged circularterminal opening 53 arranged to communicate .with the conduit 28. The air box 50 in this instance may have a circular air discharge opening stamped out from the inner wall of the flat body portion 5| and-which has adiameter equal to the hollow center through the radiator 3|, whereby a projection 56, integral with the wall opening 55,

extends therethrough a short distance and provides for support of-the radiator and imparts a heatless air transfer through the radiator to the blower unit air intake 58.

In Fig. 8 the main units of the ,heater are shown in an exploded top plan view. From an inspection of the units in disassembled condition it will be. apparent the several component parts thereof are designed for exceedingly compact assembly, in fact a'full size embodiment air-box to the apex of the cone housing and.

approximately seven inches in diameter. In the blower unit the blower wheel 46 and driving; motor "therefore are concentrically mounted vnth respectto each other and the sub-assembly mounted within the chamber defined by the two piece shell construction 48 and 48a. .The air box 50 abuts against the opposite side of the radiator 3| with the annular projection 58, of

the air box, projecting into the hollow center of the radiator locating the pieces longitudinally,

"and suitable through openings in the walls ofthe air .box provide passages forthe radiator tubes 34 and SS and location of the pieces radially. Screw means extending from the outer wall ofthe air box through the hollow center of radiator are threaded into suitable openingsfin the inner wall of the'shell section a that supports the motor "and provides means for drawwau of the air. box 50 and are arranged to extend through the dash orother wall of the vehicle The two pieces medium is being circulated through the radiator 3|, and that the valve 30 of Fig. 1 is closed, when the motor 41 is energized it will cause the centrifugal blower 46 to rotate. The blower wheel in rotating will draw air radially in through the spaced passages between the exposed fins 38 and around the core tube of the radiator 3|, and this air will be heated in passing therethrough and upon being discharged by the blower wheel through the opening 2| will be forced into the Y-fltting 22 for delivery to the interior surfaces on the windshield l9, or other desired location in the vehicle body; The above assumed set of facts and conditions of operation are predicated upon a temperature differential existing between the inside and outside of the vehicle windshield causing a deposition of the relatively humid moisture content of the passenger compartment air as it strikes the windshield and a desire to remove the resultant fog. Under a weather condition which does not cause the formation of fog or frosting of the windshield, and when it is desired to utilize the heat in warming a portion of the passenger compartment, the valve 24 may be opened thus by-passing the heated air from the opening 2| directly to the passenger compartment adjacent the driver's feet for auxiliary spot heating.

Now under a weather condition as first mentioned, namely, a dry snow storm accompanied by an atmospheric temperature near or below the'freez'lng point, as aforementioned, if heated air .is discharged against the inner face of the windshield the dry snow will become moistened or partially melted, sticking to the outer surface of the windshield and freeze thereon, when the vehicle is being driven at a moderate rate and especially so when driven at fast speeds. The conventional windshield wiper will not remedy this condition when used in conjunction with the usual windshield heater because, under the assumed weather conditions, the wiper blade only rides over the moistened snow stuck to the windshield and'tends to pack or glaze the snow thereby hastening the freezing operation. Likewise, ceasing the operation of the windshield heater which will thereby not cause the dry snow to become moistened or sticky, but will rmit its being blown away at periodic intervals by the advancing air stream when the vehicle is in mov tion, is not a satisfactory solution because there is ever present a foggi 6r steaming of the closed windows of the vehicle and especially the windshield which must be kept clear for safe driving. Therefore, assuming the conditions as above, in

' the use of the present invention the driver may open the valve3|i thereby permitting the induction of fresh outside air, through the conduit 28 and deflector 29, in response to forward motion of they vehicle. The dry fresh air is received from the inner end of the conduit 28 into the air box 50, and upon energizing the blower motor 41 the blower wheel 46 will draw air, which following the path of least resistance, will now be received from the discharge opening of the air box under pressure, and not through the passage between fins 38 of the radiator 3| as previously. The fresh air thus passing through the hollow center of the radiator undergoes substantially a heatless transfer and then passes through the openings 58 in the shell 48a where it may be picked up by the blower wheel 46 and discharged through the opening 2| into the Y-fltting 22 and distributed in untempered condition to the inner surfaces of the windshield, In so far as this applicant is aware, all other existing windshield cleaning devices designed primarily for that purpose and now available, do not contain the combined features of the present structure in the novel compact and efllcient manner disclosed.

It has been determined that recirculated, moisture-laden, heated air of the passenger compartment will not maintain the windshield clean under the above dry snow condition, however, it is also true that completely untreated dry outside air is not necessary to remove fog or steam from the windshield; so long as the air discharged over the face of the windshield has a relative humidity comparable with the relatively dry outside atmosphere that is sufficient. Accordingly, a modified form of air box generally designated 65 is illustrated in Figs. 9 and 10, for use in conjunction with the present structure and which is substantially similar to the air box 56 'hereinbefore described, therefore, like numerals are used to designate similar parts in the two members and only the variations therefrom will be' described. In this instance the air discharge opening 55, shown in the wall of air box 56, and which provided for delivery of air in a heatless transfer through the hollow center of the radiator 3|, has been left a blank and the arcuate openings 66, spaced by the radial arms 61, in the wall 68 of the air box 65 have been substituted. The openings 66 are disposed substantially on the same radius that the fins 38 of the radiator 3| are wherebywhen the air box 65 is drawn up flush to one side of the radiator, in a manner similar to that shown for air box 58 in Fig. 2, air from the box 65 will be discharged laterally into the spaces between .thefins 38 and thence radially inward through the hollow center of the radiator and through the openings 58 of the blower housing 48a where the centrifugal blower 46 picks up the air and discharges thesame to a selected location, assuming of course that the motor 41 has been energized.

In the operation of the structure just-described fresh outside air is deflected by the air scoop 28, extending from the cowl of the vehicle and is inducted through'the conduit 28 in communication therewith at its outer end and the air box 65 at its inner end, in response to forward motion of the vehicle. Air under pressure in the box 65 will be forced through the arcuate openings 66 laterally into the spaces between the fins 38 to wipe the heat conducting surfaces thereof and thence radially inward into the hollow center of the radiator, assuming the blower unit 45 is operating and causing an area of reduced pressure therein which the air following the path of least resistance would normally take. From the interior of the'radiator 3| the heated air is-drawn through theopenings 58 of the blower housing section 48a where the centrifugal blower 46 picks it up and discharges the same through the opening 2| for distribution to the surfaces of the windshield, orselectively, through the bypass valve 34 for delivery direct to the passenger compartment. Optionally the valve 30 may be closed, as in the first structure, and only recirculated air may be used, in which case the air is drawn radially inward between the spaced fins 38 into the center of the radiator 3| and thence through the openin s 58 to the blower wheel 46 where it may be selectively discharged for delivery to surfaces of the windshield I! or through the by-pass valve24 directly to the passenger 1 I i .one core tube -,and terminating in axially spaced faces, a plu-' particularly in connection with a windshield heater forwhich use it is primarily intended, it will be understood that portions or all of'the presently suggested structures inight be advantageously utilised in connection with lieat exchange in general. Moreover, numerous changes in construction and rearrangement of the parts might be resortedto without departing from the. spirit of the invention as defined by the claims.

WhatI.claimis:

1. In an automotive vehicle windshield derfroster of the character described including a heater core, conduit means including a valve therein arranged to induct fresh outside air in response to forward motion of the vehicle, said core comprising a single core tube defining an annular unobstructed ,air channel through the.

centerthereof and including aplurality of sep;

arate heat radiating fins closely assembled on 20 tially radially disposed air flow passagesinto the said core tube providing a plurality of substanhollow center of said core, an air collectin housingsecured ahtlyagainstthefinsoncneface "of said core and having an intake opening in 'commimication with said conduit means'and a discharge opening in registration with the central air channel of said core, an air impeller means includingan assoeiated'housing to said air collectint housing. and spaced therefrcm by the firms on the opposite face of said coretodrawairfromtheairjchannel'o'fsaid core, and to distributethe same through one'or' more conduits to the surface of the vehicle windshield, said conduit valve meansywhen in an 35 open position, permitting fresh outsidev air to pass through the central air channel of thecore in unheated condition in said impeller and when in closed position cutting offthe fresh air supply whereby said impeller may draw vehicle air only through said core by way ofthe radial passages 49 betweenthefins. r v I 2. In an apparatus of the character described, a heater core, said core comprised of at least defining a relatively narrow cylindricaibody having a hollow center therethrough ing in registration with the hollowcenter of saidcore,- and means for driving, said air impeller causingmovementofairaxiallyfromsaidair,

asse a box in a substantially heatless transfer through l the hollow center of said core, or selectively, radially through the air spaces between said heat radially disposed spaced fins providing heat' radiating fins according to the degree of resistance imposed upon the air stream.

3. In an automotive vehicleapparatus of the character described including a finned heater core having spaced axial faces,-saidcorehaving separate-air channels therethrough defining acentral annular unobstructed air channel and transfer passages, respectively, said heat transfer passages of the core having greater resist- .ance to air .movement therethrough'than said central air channel, means including an air box secured tightly against the fins on one axial face of said core for inducting fresh... outside airto I said core in response to forward motion of the vehicle, a control valve for said fresh air means, permitting passage of unheated freshair through the air channel of the core to the vehicle compartment and, when in a closed position, to pro- .vide for passage of recirculated heated. air

through said radially heat transfer passages of the core, and air impeller means secured tightly against the fins on the opposite axial face .of said core and effecting movement of tempered or untempered air radially and/or axially "through thecore according to the degree of re- 30 sistance imposed thereon by said control valve.

4. In an automotive vehicle windshield heater or defroster including a finned heater core. having spaced axial faces, said core having separate air channels-therethrough'defininga central annular unobstructed air channel and radially disposed spaced fins providing-heat transfer pas sages respectively, said heat transfer passages of the core being open to thevehicle compartment and having 'greaterresistance to air movement therethrough than said central air channel,

' means including an air box secured'-tightly against the fins on one axial face of said core and including a control valve for inducting fresh outside air tosaid core. in response, to forward motion of the vehicle, air impeller means including. associated housing secured tightlyagainst the fins on the opposite'axial face of said core to draw heated air through said radial heat transfer passages and central air channel of the core when said fresh air control valve is closed andiunheated fresh airthrough said central air ofthe core when said control valve is channel opened.-and said housing havin one or more discharge openings for delivery of heated or unheated fresh air to the surface of thewindshield or tothe passenger compartment, selectively, and

in accordance with said control valve position.

' now'mp J. 

